Method of forming fluid passages



g- 8, 1967 P. o. w. HOPKINSON, JR 3,334,401

METHOD OF FORMING FLUID PASSAGES Filed March 4, 1965 I r [I l 7 I I l I91.] I

F H a; 1 1H JNVENTOR. 5 J x P404 01/1 5214. HOHWA/SO/V, JQ.

Z Z r 4 BY United States Patent 3,334,401 METHOD OF FORMING FLUIDPASSAGES Paul Oliver W. Hopkinson, Jr., Gibsonia, Pa., assignor to St.Barnabas Brotherhood, Inc., Gibsonia, Pa., a corporation of PennsylvaniaFiled Mar. 4, 1965, Ser. No. 437,150 3 Claims. (Cl; 29--157) Thisinvention relates to the formation of short fluid passages, and moreparticularly complex passages such as used in fluid amplifiers.

In fluid amplifiers a stream of fluid is delivered to the outer end ofthe stem of a Y-shape passage, the outer ends of the branches of whichform outlets. To direct the fluid into the desired branch, there are apair of lateral passages that open into the stem of the Y. A controlfluid under pressure directed into the outer end of either of thesebranch passages will divert the main fluid stream into one or the otherof the branches of the Y-shape passage. A common way of forming suchpassages heretofore has been to etch channels having their shape in oneside of a plate and then bond thereto another plate in order to coverthe channels. The inlets and outlets of the passages thus formedtherefore are located at the edges of the plates.

It is among the objects of this invention to provide a method of forminga fluid passage, which is simpler and less expensive than etching, whichcan produce passages very rapidly, and which can form them in anydesired shape.

In accordance with this invention, a flat sheet is cut to remove asection from it that forms in the sheet a slot having closed ends. Theslotted sheet then is scaled between a pair of backing members thatcover all of the slot except its ends, so that the ends of the sheetwill project from between the two backing members. The projecting endsof the sheet then are removed in order to open the ends of the slot andthereby form a through passage between the backing members. Preferably,the sheet that is slotted is made from a gasket material and the slot isformed by a punching operation.

The invention is illustrated in the accompanying drawings, in which:

FIG. 1 is an oblique view of a sheet that is to be punched;

FIG. 2 is an end view of the sheet between dies that will punch asection out of it;

FIG. 3 is a plan view of the sheet after it has been stamped, showingthe opening that has been formed;

FIG. 4 is a plan View of the sheet between two backing members;

FIG. 5 is an end view of the assembly, showing the projecting portion ofthe sheet about to be trimmed off;

FIG. 6 is an oblique view of the assembly with the marginal area of thesheet removed to expose the ends of the passages; and

FIG. 7 is a plan view of the finished device, with the passages shown indotted lines.

Referring to the drawings, a sheet 1 of suitable material that is largerthan the desired passage is selected. The sheet should be the samethickness as the desired passage. Different materials may be used forthe sheet, such as subber, plastic and even metal, but a very suitablematerial is that from which cylinder gaskets are made for automobiles.Suitable means for cutting an opening of the desired shape in the sheetis provided. Most suitably, this means consists of a pair of dies forpunching out a section of the sheet in order to leave the desiredopening. Such dies are indicated in FIG. 2, where the sheet is shownresting on the lower die 2 and about to be punched by the upper die 3.After the sheet has been punched it may look like the one shown in FIG.3, al-

though a single straight slot or an opening of some other shape could beformed just as well, depending upon the use. The opening shown isintended to be formed into passages for a fluid amplifier. It will beseen that it is generally Y-shaped with a stem 4 and two divergingbranches 5. Also, behind the point where the branches join the stem,there is a pair of laterally projecting arms 6 communicating with thestern. It should be noted that at no place has the sheet been cutthrough to its edge. In other words, the outer ends of the extremetiesof the opening or slot are all closed and spaced from the edges of thesheet. This permits the sheet to be handled as a unit instead of severalseparate pieces that would have to be assembled and arranged.

The next step, as shown in FIG. 4, is to place the slotted sheet betweena pair of backing members 8 that preferably are rigid. These may beeither thin or thick plates of any suitable material. The plates aresmaller than the punched sheet so that they leave the marginal portionsof the sheet projecting from between them in all directions just farenough to expose the ends of the slots. The plates are bonded to thesheet in any suitable manner to seal them together. Then the projectingmarginal portions of the sheet are removed, such as by trimming them offby knives 9 as shown in FIG. 5. The resulting product shown in FIGS. 6and 7 is a sandwich in which the three parts all have the same lengthand width. By removing the projecting portions of the sheet, the ends ofits opening are opened and exposed for connection in any suitable mannerto fluid conduits. The

opening in the sheet between the two plates now has.

become connected through-passages, two opposite walls of which areformed by the plates.

It will be seen that passages of any desired shape can be formed in thismanner very quickly and inexpensively in great numbers after dies of theproper configuration have been made.

According to the provisions of the patent statutes, I have explained theprinciple of my invention and have illustrated and described what I nowconsider to represent its best embodiment. However, I desire to have itunderstood that, Within the scope of the appended claims, the inventionmay be practiced otherwise than as specifically illustrated anddescribed.

I claim:

1. The method of forming a fluid passage, comprising cutting a flatsheet to remove a section therefrom that forms in the sheet a slothaving closed ends, sealing the slotted sheet between a pair of backingmembers that cover all of said slot except its ends so that the ends ofthe sheet project from between said members, and then removing saidprojecting ends of the sheet to open the ends of the slot and therebyform a through-passage between said backing members.

2. The method of forming a fluid passage, comprising punching out of aflat sheet a section thereof to form in the sheet an opening having endsthat are closed, sealing the punched sheet between a pair of backingmembers that cover all of said opening except its ends so that themarginal portions of the sheet containing said closed ends project frombetween said members, and then trimming off said marginal portions ofthe sheet to open the ends of said opening and thereby form athrough-passage between said backing members.

3. The method of making fluid amplifier fluid passages, comprisingpunching out of a flat sheet a section that is Y-shape with laterallyprojecting arms connected to the stem of the Y, said section being smallenough for the opening left by it in the sheet to have the outer ends ofits stern and branches and arms closed, placing the punched she'etbetween a pair of rigid backing members that cover all of said openingexcept said outer ends so I 3 4 that the marginal portions of the sheetproject from 2,644,665 7/1953 Cangeni 29-1573 X beneath said members,and then trimming off said mar- 2,704,882 3/1955 Olson 29418 X ginalportions of the sheet to open the outer ends of 3,144,037 8/1964 Cargillet a1. 13781.5 said opening and thereby form through-passages be-3,168,897 2/1965 Adams et a1 13781.5 tween said backing members. 53,282,297 11/ 1966 Bauer 13781.5 X

References Cited EIGN PATENTS UNITED STATES PATENTS 1,369,417 7/1964France. 1,642,426 9/ 1927 Risinger. CHARLIE T. MOON, Primary Examiner.

1. THE METHOD OF FORMING A FLUID PASSAGE, COMPRISING CUTTING A FLATSHEET TO REMOVE A SECTION THEREFROM THAT FORMS IN THE SHEET A SLOTHAVING CLOSED ENDS, SEALING THE SLOTTED SHEET BETWEEN A PAIR OF BACKINGMEMBERS THAT COVER ALL OF SAID SLOT EXCEPT ITS ENDS SO THAT THE ENDS OFTHE SHEET PROJECT FROM BETWEEN SAID MEMBERS, AND THEN REMOVING SAIDPROJECTING ENDS OF THE SHEET TO OPEN THE ENDS OF THE SLOT AND THEREBYFORM A THROUGH-PASSAGE BETWEEN SAID BACKING MEMBERS.